Influence Of The Incident Direction Of Seismic Wave On Dynamic Response Of Slope

As a marginal subject, dynamic response of slope is not only an important problem ofengineering geology, but also of other subjects such as engineering seismic and geotechnicalengineering. In our country, owing to special geographic conditions and geological conditions, theproblem of seismic slope is prominent.Seismic dynamic response of slope is affected by the properties of slope and behaves ofseismic dynamic as the leading role. The way of ground motion includes the direction andproperties of seismic dynamic and the three elements of seismic wave. When the incident directionof seismic wave, the dynamic action mode changes too, at the same time the dynamic responses ofslope are different. At present in the research of earthquake slope, the effect of the incidentdirection of seismic wave on the slope dynamic response is not reported.The finite difference software named FLAC3Dis utilized. Using load increasing method, theinfluence of the incident directions of seismic wave on dynamic response of slope and slope’searthquake peak acceleration of damage is simulated.Seismic waves obliquely incident excitation in slope seismic dynamic response of thenumerical simulation is still unsolved. Considering different particle vibration mode phases andthe physical relationship between seismic wave displacement and stress, the Azimuth angle ofincidence and the incident two parameters using seismic waves are used to develop a method ofoblique incidence seismic excitation. This moves the obstacles that block the development ofoblique incidence of seismic ground motion excitation slope dynamic response numericalsimulation.On the basis of technology of the oblique incidence, the dynamic response and criticalearthquake acceleration of homogeneous slope with different top form such as flat, convex andconcave are simulated by FLAC3D. Further simulation of dynamic response critical acceleration ofPanlongyuan loess slope to ground motion with different incident directions is conducted. Bydoing these some recognition and fruits have achieved as followed:(1) When the earthquake strength is small, The directions of the first motion of seismic wave haveno effect on the dynamic response of slope; But when earthquake intensity is bigger, seismicwaves moving direction at the beginning have a great influence on dynamic response of theslope.(2) The slopes have different critical seismic acceleration, if they have different top form.(3) When seismic waves’ incident angle and azimuth are different, the critical earthquake peakacceleration of slope will change.(4) The critical earthquake peak acceleration of slope can be influenced by the type of seismicwave phases. Moreover the sensitivity of seismic wave’s incident angle and azimuth to thedynamic response are related to seismic phase and the top form of slope.